1. Field of the Invention
The present invention relates to a radiation clinical thermometer for measuring a body temperature by measuring an amount of infrared light radiated from a living body, and a method of measuring the temperature.
2. Description of the Related Art
Conventionally, as this type of radiation clinical thermometer, there is an aural clinical thermometer for determining a body temperature by measuring an amount of infrared light radiated from an eardrum.
In such an aural clinical thermometer, in order to measure an accurate body temperature, it is necessary that a probe is inserted in an ear and a detecting surface of an infrared sensor is correctly directed toward an eardrum, that is, a probe is correctly directed toward the eardrum.
Thus, as is disclosed in Japanese Patent Application Laid-open No. Hei. 7-286905, there is a clinical thermometer in which an illuminating device is provided so that a position of an eardrum can be confirmed before measurement. Further, as is disclosed in Japanese Patent Application Laid-open No. Hei. 7-47057, there is a clinical thermometer in which a finder is provided so that it is possible to confirm whether a probe is inserted at a position where an eardrum can be seen. Further, as is disclosed in Japanese Patent Application Laid-open No. Hei. 6-142062, there is a clinical thermometer in which a field of view of an infrared sensor can be confirmed by using a movable mirror. Further, as is disclosed in Japanese Patent Application Laid-open No. Hei. 9-5167, there is a clinical thermometer in which a visible light lamp and a reflecting mirror are provided so that an eardrum can be seen by the eyes.
Any of these clinical thermometers are designed such that a person other than a user can confirm a position of an eardrum, and any of these are not realized, and even if they are realized, they become very expensive so that they are difficult to adopt.
That is, there is no means for enabling a user himself to confirm whether or not a probe is correctly inserted toward an eardrum.
In a conventional aural clinical thermometer, a measurement value of a body temperature is obtained by a procedure as shown in FIG. 12. That is, a power source is turned on (step 101), and after a probe of a clinical thermometer is inserted in an ear (step 102), a measurement switch is pressed (step 103), so that there occurs a transition to a measurement operation of carrying out A/D conversion or the like of a sensor signal (step 104), a body temperature is calculated by using the A/D conversion value (step 105), and the body temperature is displayed (step 106). At this time, as a measurement method, there is generally adopted a system in which sampling is carried out plural times to perform A/D conversion at step 104 and an average value of the plurality of A/D conversion values is used at step 105, or a peak hold system (see Japanese Patent Application Laid-open No. Hei. 8-215154) in which a body temperature is determined by using a peak value among the plurality of A/D conversion values. In the peak hold system like this, since the peak value of measurement temperature is used to calculate the body temperature, there is a high probability that a temperature when a probe is directed toward an eardrum is obtained. Also, by FIG. 13 showing a temperature distribution with respect to an eardrum and an external auditory meatus, it is indicated that the temperature of the eardrum is highest in an ear, and the temperature of the eardrum can be measured at a high probability by obtaining the peak value (FIG. 13 shows actually measured data of eight testees, which are normalized while the temperature of the eardrum is made 37xc2x0 C. Here, xe2x80x9cMeanxe2x80x9d indicates an average value, and xe2x80x9cSDxe2x80x9d indicates a standard deviation). Like this, even in the conventional method, it is possible to get the temperature of the eardrum more accurately by measurement and calculation.
However, in the foregoing conventional technique, although there is a high probability that a temperature when a probe is correctly directed toward an eardrum can be measured by the measurement method, since the user can not know when the probe is correctly directed toward the eardrum, in order to recognize a correct insertion position of the probe, an experience of making measurement plural times is necessary, and there is a problem that when measurement can be made only one time as in the case where the body temperatures of unspecified many patients are measured in a hospital, it is hard to obtain a correct measurement value.
The present invention has been made to solve the problem of the conventional technique, and an object thereof is to provide a radiation clinical thermometer in which an accurate body temperature can be easily and quickly measured without requiring any experience since a user recognizes that a probe is correctly directed toward an eardrum.
In order to achieve the above object, according to the present invention, a radiation clinical thermometer comprises temperature measurement means for measuring a temperature of a measurement object on the basis of an amount of infrared light radiated from the measurement object, a probe to be inserted in an ear of a user, insertion state determination means for determining an insertion state of the probe, and notification means for notifying the user of the insertion state of the probe.
With the above construction, since the user can recognize the insertion state of the probe, experience is not needed to correctly direct the probe toward the eardrum, and an accurate body temperature can be easily and quickly measured.
The insertion state determination means may determine the insertion state of the probe by a variation pattern of measured temperature.
Further, the insertion state determination means may determine whether or not the probe is inserted in the ear.
Further, the temperature measurement means may start a body temperature measurement processing on the basis of the determined insertion state of the probe.
Further, the insertion state determination means may have a function to determine whether or not the insertion state of the probe is an insertion state suitable for body temperature measurement, and a period of time for which a determination is performed may be prolonged in accordance with a determination result of the insertion state in a predetermined time.
Further, in the case where the period of time for which the determination is performed is prolonged, a determination criterion of the insertion state of the probe may be changed.
Further, the notification means may have a function to notify the insertion state of the probe stepwise.
Further, display means for displaying a measurement result may be provided, and after completion of a body temperature measurement processing, the insertion state of the probe at the time of the measurement, together with a measurement value, may be displayed on the display means.
Further, the temperature measurement means may have a function to correct a measurement value on the basis of the insertion state of the probe at the time of measurement.
Further, according to the present invention, a method of measuring a body temperature using a radiation clinical thermometer in which a probe is inserted in an ear and a temperature of a measurement object is measured on the basis of an amount of infrared light radiated from the measurement object, comprises a step of measuring the temperature of the measurement object toward which the inserted probe is directed, a step of judging whether or not a measured temperature value is within a predetermined temperature range, and a step in which in a case where the measured value is within the predetermined temperature range, it is determined that the probe has been inserted in the ear and this is notified to the user.
Further, according to the present invention, a method of measuring a body temperature using a radiation clinical thermometer in which a probe is inserted in an ear and a temperature of a measurement object is measured on the basis of an amount of infrared light radiated from the measurement object, comprises a step of measuring the temperature of the measurement object toward which the inserted probe is directed, a step of recognizing a variation pattern of measured temperature values, a step of relating a predetermined variation pattern of the measured temperature values to an insertion state of the probe, and a step of notifying a user of the related insertion state of the probe.
Further, the variation pattern of the temperature measurement values related to the insertion state of the probe may be a pattern in which a relative or local maximum value appears in the temperature measurement values.
Further, the insertion state of the probe suitable for body temperature measurement may be related to a variation pattern in which two relative or local maximum values consecutively appear in the temperature measurement values from a predetermined point of time.